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Violent respiratory events play critical roles in the transmission of respiratory diseases, such as coughing and sneezing, between infectious and susceptible individuals. In this work, large-scale multiphase flow large-eddy simulations have been performed to simulate the coughing jet from a human's mouth carrying pathogenic or virus-laden droplets by using a weakly compressible smoothed particle hydrodynamics method. We explicitly model the cough jet ejected from a human mouth in the form of a mixture of two-phase fluids based on the cough velocity profile of the exhalation flow obtained from experimental data and the statistics of the droplets’ sizes. The coupling and interaction between the two expiratory phases and ambient surrounding air are examined based on the interaction between the gas particles and droplet particles. First, the results reveal that the turbulence of the cough jet determines the dispersion of the virus-laden droplets, i.e. whether they fly up evolving into aerosols or fall down to the ground. Second, the droplet particles have significant effects on the evolution of the cough jet turbulence; for example, they increase the complexity and butterfly effect introduced by the turbulence disturbance. Our results show that the prediction of the spreading distance of droplet particles often goes beyond the social distancing rules recommended by the World Health Organization, which reminds us of the risks of exposure if we do not take any protecting protocol.
This study evaluated the association between inflammatory diets as measured by the dietary inflammatory index (DII), and inflammation biomarkers, and the development of preeclampsia among the Chinese population. We followed the reporting guidelines of the STROBE statement for observational studies. A total of 466 preeclampsia cases aged over 18 years were recruited between March 2016 and June 2019, and 466 healthy controls were 1:1 ratio matched by age (± 3 years), week of gestation (± 1 week), and gestational diabetes mellitus. The energy-adjusted DII (E-DII) was computed based on dietary intake assessed using a 79-item semiquantitative food frequency questionnaire (FFQ). Inflammatory biomarkers were analyzed by ELISA kits. The mean E-DII scores were -0.65 ± 1.58 for cases and -1.19 ± 1.47 for controls (P value <0.001). E-DII scores positively correlated with IFN-γ (rs = 0.194, P value = 0.001) and IL-4 (rs = 0.135, P value = 0.021). After multivariable adjustment, E-DII scores were positively related to preeclampsia risk (P trend <0.001). The highest tertile of E-DII was 2.18 times the lowest tertiles (95% CI = 1.52, 3.13). The odds of preeclampsia increased by 30% (95% CI= 18%, 43%, P value <0.001) for each E-DII score increase. The preeclampsia risk was positively associated with IL-2 (OR = 1.07, 95% CI = 1.03, 1.11), IL-4 (OR = 1.26, 95% CI = 1.03, 1.54) and TGF-β (OR = 1.17, 95% CI = 1.06, 1.29). Therefore, proinflammatory diets, corresponding to higher IL-2, IL-4 and TGF-β levels, were associated with increased preeclampsia risk.
The aim of this work was to develop a table-top exercise (TTX) program for mass-casualty incident (MCI) response based on a real incident to evaluate the program.
Methods:
The TTX program was developed based on the 8 TTX design steps. Convenience sampling was adopted to recruit recently graduated physicians in China. After the TTX training, the participants completed a self-designed questionnaire, as well as the Simulation Design Scale (SDS) and Educational Practices in Simulation Scale (EPSS).
Results:
In total, 148 valid questionnaires were collected. The difficulty score of the TTX program was 3.69 ± 0.8. The participants evaluated the program highly, with a score of 4.72 ± 0.54 out of 5. Both the SDS and the EPSS had average scores higher than 4.5. Guided reflection/feedback (M = 4.68, SD = 0.41) and fidelity (M =4.66, SD = 0.57) were the 2 highest-rated SDS subscales. For the EPSS, diverse ways of learning and collaboration were the 2 highest-rated subscales. Multivariate stepwise regression analysis showed that the participants’ evaluations of the TTX training course were related to the EPSS score, the difficulty rating, the evaluation of the instructional props, and the degree of participant involvement (F = 24.385, P < 0.001).
Conclusions:
A TTX program for MCIs was developed based on the 2014 Shanghai New Year Crush. The TTX kit is practical and sophisticated, and it provides an effective strategy for MCI training.
Lower-crust-derived adakitic rocks in the Gangdese belt provide important constraints on the timing of Tibetan crustal thickening and on the relative contributions of magmatic and tectonic processes. Here we present geochronological and geochemical data for the Wangdui porphyritic monzogranites in the western Gangdese belt. Zircon U–Pb dating yields emplacement ages of 46–44 Ma. All samples have high Sr (321–599 ppm), low Yb (0.76–1.33 ppm) and Y (10.6–18.3 ppm) contents, with high La/Yb (51.1–72.3) and Sr/Y (21.0–51.4) ratios, indicating adakitic affinities. The low MgO (0.97–1.76 wt %), Cr (7.49–53.6 ppm) and Ni (4.75–29.1 ppm) contents, as well as high 87Sr/86Sr(i) (0.7143–0.7145), low ϵNd(t) (−10.4 to −9.8) and zircon ϵHf(t) (−17.7 to 0.4) values, suggest that the Wangdui pluton most likely originated from partial melting of the thickened ancient lower crust. In combination with previously published data, despite the east–west-trending heterogeneity of crustal composition in the Gangdese belt, the La/Yb ratios of magmatic rocks reveal that both western and eastern segments experienced remarkable crustal thickening in the Eocene. However, in contrast to the thickened juvenile lower crust in the eastern segment formed by the underplating of mantle-derived magmas, tectonic shortening plays a more crucial role in thickening of the ancient basement in western Gangdese. In fact, such Eocene-thickened ancient lower-crust-derived adakitic rocks are widely distributed in the central Himalayan–Tibetan orogen. This, together with the extensive development of fold–thrust belts, suggests that tectonic shortening might be the main mechanism accounting for the crustal thickening associated with the India–Asia collision.
Direct numerical simulations of a three-dimensional cylindrical Richtmyer–Meshkov instability with and without chemical reactions are carried out to explore the chemical reaction effects on the statistical characteristics of transition and turbulent mixing. We adopt 9-species and 19-reaction models of non-premixed hydrogen and oxygen separated by a multimode perturbed cylindrical interface. A new definition of mixing width suitable for a chemical reaction is introduced, and we investigate the spatio-temporal evolution of typical flow parameters within the mixing regions. After reshock with a fuller mixing of fuels and oxygen, the chemical reaction becomes sufficiently apparent at affecting the evolution of the flow fields. Because of the generation of a combustion wave within the combustion regions and propagation, the growth of the mixing width with a chemical reaction is accelerated, especially around the outer radius with large temperature gradient profiles. However, the viscous dissipation rate in the early stage of the chemical reaction is greater because of heat release, which results in weakened turbulent mixing within the mixing regions. We confirm that small-scale structures begin to develop after reshock and then decay over time. During the developing process, helicity also begins to develop, in addition to kinetic energy, viscous dissipation rate, enstrophy, etc. In the present numerical simulations with cylindrical geometry, the fluctuating flow fields evolve from quasi-two-dimensional perturbations, and the generations of helicity can capture this transition process. The weakened fluctuations during shock compression can be explained as the inverse energy cascade, and the chemical reaction can promote this inverse energy cascade process.
The extinct family Hylicellidae, as the ancestral group of modern cicadomorphans, had a wide distribution and a very high species-level biodiversity from the Triassic to Early Cretaceous. We herein report 11 new hylicellid specimens from the Jurassic Daohugou beds of Inner Mongolia, NE China, and execute geometric morphometric analysis (GMA) to elucidate their systematic position. Our GMA and subsequent morphometric statistics indicate that 10 of our new specimens can be compared to the holotype of Cycloscytina gobiensis, and one is new to science. Cycloscytina incompleta new species is erected based on this specimen, with the following discriminatory tegminal traits: C3 almost as long as and slightly narrower than C2, and the forking position of stem M distinctly migrates towards wing apex and much apicad of the stem CuA bifurcating. Additionally, Cycloscytina plachutai is herein transferred to the procercopid genus Procercopina, resulting in P. plachutai new combination. To date, just a few body structures of Hylicellidae have been revealed, and the new whole-bodied hylicellids reported herein provide some novel insights on the evolution of basal Clypeata. This study also emphasizes the use of morphometric analysis in the systematics of wing-bearing insects such as hylicellids.
The mumps resurgence has frequently been reported around the world in recent years, especially in many counties mumps vaccines have been widely used. This study aimed to describe the spatial epidemiological characteristics of mumps in Jiangsu, and provide a scientific basis for the implementation and adjustment of strategies to prevent and control mumps. The epidemiological characteristics were described with ratio or proportion. Spatial autocorrelation, Tango's flexible spatial scan statistics, and Kulldorff's elliptic spatiotemporal scan statistics were applied to identify the spatial autocorrelation, detect hot and cold spots of mumps incidence, and aggregation areas. A total of 172 775 cases were reported from 2004 to 2020 in Jiangsu. The general trend of mumps incidence is declining with a bimodal seasonal distribution identified mainly in summer and winter, respectively. Children aged 5–10 years old are the main risk group. A migration trend of hot spots from southeast to northwest over time was found. Similar high-risk aggregations were detected in the northwestern parts through spatial-temporal analysis with the most likely cluster time frame around 2019. Local medical and health administrations should formulate and implement targeted health care policies and allocate health resources more appropriately corresponding to the epidemiological characteristics of mumps.
Helicity is a quadratic inviscid conservative quantity in three-dimensional turbulent flows and is crucial for turbulent system evolution. Helicity effects have mainly been highlighted over the past few decades to explore the intrinsic mechanism of turbulent flows, while the statistical characteristics of helicity itself are nearly absent in general anisotropic turbulent flows. In this paper, we investigate the helicity statistics in turbulent channel flows with streamwise rotation at moderate rotation numbers ($Ro_{\tau }=7.5,15$ and 30) and Reynolds numbers ($Re_{\tau }=180$ and 395), including their spatial and scale distributions, anisotropy and cross-scale transfer. The appearance of a mean secondary flow in the spanwise direction corresponds to a mean streamwise vorticity, which indicates the presence of a high-helicity distribution. Numerical results reveal a regular helicity profile along the wall-normal direction, and a new peak is found in the near-wall region around $y^+=6$ of the streamwise or spanwise helicity profiles. The inter-scale helicity transfer is analysed by the filtering method, and the numerical consequences reveal that the second channel of the helicity cascade we proposed previously is dominant in contrast to the first channel. The rotation effects are explored by comparing the numerical results obtained under different rotation numbers. With increasing rotation number, more helical structures in the near-wall regions are present, with peaks of helicity profiles and fluxes coming closer to the wall. With a higher Reynolds number, their amplitudes are larger and scale-space transfer is strengthened. These systematic numerical analyses uncover the helicity distributions and transfer in wall-bounded turbulent flows.
The role of neurological proteins in the development of bipolar disorder (BD) and schizophrenia (SCZ) remains elusive now. The current study aims to explore the potential genetic correlations of plasma neurological proteins with BD and SCZ.
Methods:
By using the latest genome-wide association study (GWAS) summary data of BD and SCZ (including 41,917 BD cases, 11,260 SCZ cases, and 396,091 controls) derived from the Psychiatric GWAS Consortium website (PGC) and a recently released GWAS of neurological proteins (including 750 individuals), we performed a linkage disequilibrium score regression (LDSC) analysis to detect the potential genetic correlations between the two common psychiatric disorders and each of the 92 neurological proteins. Two-sample Mendelian randomisation (MR) analysis was then applied to assess the bidirectional causal relationship between the neurological proteins identified by LDSC, BD and SCZ.
Results:
LDSC analysis identified one neurological protein, NEP, which shows suggestive genetic correlation signals for both BD (coefficient = −0.165, p value = 0.035) and SCZ (coefficient = −0.235, p value = 0.020). However, those association did not remain significant after strict Bonferroni correction. Two sample MR analysis found that there was an association between genetically predicted level of NEP protein, BD (odd ratio [OR] = 0.87, p value = 1.61 × 10−6) and SCZ (OR = 0.90, p value = 4.04 × 10−6). However, in the opposite direction, there is no genetically predicted association between BD, SCZ, and NEP protein level.
Conclusion:
This study provided novel clues for understanding the genetic effects of neurological proteins on BD and SCZ.
Risk perception among nurses after the COVID-19 pandemic is a crucial factor affecting their attitudes and willingness to work in clinics. Those with poor psychological status could perceive risks sensitively as fears or threats that are discouraging. This article aimed to determine whether psychological outcomes, including post-traumatic stress disorder (PTSD), depression, anxiety, and insomnia, following the COVID-19 pandemic were differentially related to the risk perceptions of nurses working in clinics and increased perceived risk.
Method
The participants were 668 nurse clinicians from five local hospitals. Risk perceptions and psychological outcomes were measured by adapted questionnaires via the Internet. Latent profile analysis (LPA) identified subgroups of individuals who showed similar profiles regarding the perceived risks in nursing. Multinomial regression and probit regression were used to examine the extent to which sociodemographic and psychological outcomes predicted class membership.
Results
LPA revealed four classes: groups with low-, mild-, moderate-, and high-level risk perceptions. Membership of the high-level risk perception class was predicted by the severity of psychological outcomes. Anxiety significantly accounted for a moderate increase in risk perceptions, while the symptoms of insomnia, depression, and PTSD accelerated the increase to the high level of risk perception class.
Conclusions
By classifying groups of nurse clinicians sharing similar profiles regarding risk perceptions and then exploring associated predictors, this study shows the psychological outcomes after COVID-19 significantly impacted pandemic-associated risk perceptions and suggests intervening in nurses' psychological outcomes while simultaneously focusing on work-related worries is important following the outbreak of COVID-19.
Tumors have posed a serious threat to human life and health. Researchers can determine whether or not cells are cancerous, whether the cancer cells are invasive or metastatic, and what the effects of drugs are on cancer cells by the physical properties such as hardness, adhesion, and Young's modulus. The atomic force microscope (AFM) has emerged as a key important tool for biomechanics research on tumor cells due to its ability to image and collect force spectroscopy information of biological samples with nano-level spatial resolution and under near-physiological conditions. This article reviews the existing results of the study of cancer cells with AFM. The main foci are the operating principle of AFM and research advances in mechanical property measurement, ultra-microtopography, and molecular recognition of tumor cells, which allows us to outline what we do know it in a systematic way and to summarize and to discuss future directions.
An understanding of how the money market developed is vital because money serves as the blood of an economy. From 1800 to 1937, the Chinese money market transitioned from a highly fragmented bimetallic system to a gradually integrated silver yuan system in tandem with a silver-backed fiduciary paper-money system until a fiat money system was established. As a consequence, the economy became increasingly monetized as the growth rate of the money supply gradually surpassed the overall economic growth rate without evident inflation pressure on general price trends. This development resulted both from the efforts of governments and private institutions in response to various types of shock separately and from the outcomes of competition and co-operation between the two stakeholders over time.
Neuroimaging studies on major depressive disorder (MDD) have identified an extensive range of brain structural abnormalities, but the exact neural mechanisms associated with MDD remain elusive. Most previous studies were performed with voxel- or surface-based morphometry which were univariate methods without considering spatial information across voxels/vertices.
Methods
Brain morphology was investigated using voxel-based morphometry (VBM) and source-based morphometry (SBM) in 1082 MDD patients and 990 healthy controls (HCs) from the REST-meta-MDD Consortium. We first examined group differences in regional grey matter (GM) volumes and structural covariance networks between patients and HCs. We then compared first-episode, drug-naïve (FEDN) patients, and recurrent patients. Additionally, we assessed the effects of symptom severity and illness duration on brain alterations.
Results
VBM showed decreased GM volume in various regions in MDD patients including the superior temporal cortex, anterior and middle cingulate cortex, inferior frontal cortex, and precuneus. SBM returned differences only in the prefrontal network. Comparisons between FEDN and recurrent MDD patients showed no significant differences by VBM, but SBM showed greater decreases in prefrontal, basal ganglia, visual, and cerebellar networks in the recurrent group. Moreover, depression severity was associated with volumes in the inferior frontal gyrus and precuneus, as well as the prefrontal network.
Conclusions
Simultaneous application of VBM and SBM methods revealed brain alterations in MDD patients and specified differences between recurrent and FEDN patients, which tentatively provide an effective multivariate method to identify potential neurobiological markers for depression.
Previous analyses of grey and white matter volumes have reported that schizophrenia is associated with structural changes. Deep learning is a data-driven approach that can capture highly compact hierarchical non-linear relationships among high-dimensional features, and therefore can facilitate the development of clinical tools for making a more accurate and earlier diagnosis of schizophrenia.
Aims
To identify consistent grey matter abnormalities in patients with schizophrenia, 662 people with schizophrenia and 613 healthy controls were recruited from eight centres across China, and the data from these independent sites were used to validate deep-learning classifiers.
Method
We used a prospective image-based meta-analysis of whole-brain voxel-based morphometry. We also automatically differentiated patients with schizophrenia from healthy controls using combined grey matter, white matter and cerebrospinal fluid volumetric features, incorporated a deep neural network approach on an individual basis, and tested the generalisability of the classification models using independent validation sites.
Results
We found that statistically reliable schizophrenia-related grey matter abnormalities primarily occurred in regions that included the superior temporal gyrus extending to the temporal pole, insular cortex, orbital and middle frontal cortices, middle cingulum and thalamus. Evaluated using leave-one-site-out cross-validation, the performance of the classification of schizophrenia achieved by our findings from eight independent research sites were: accuracy, 77.19–85.74%; sensitivity, 75.31–89.29% and area under the receiver operating characteristic curve, 0.797–0.909.
Conclusions
These results suggest that, by using deep-learning techniques, multidimensional neuroanatomical changes in schizophrenia are capable of robustly discriminating patients with schizophrenia from healthy controls, findings which could facilitate clinical diagnosis and treatment in schizophrenia.
We aimed to investigate the coronavirus disease 2019 (COVID-19)-related knowledge and practices of cancer patients and to assess their anxiety- and depression-related to COVID-19 during the early surge phase of the pandemic.
Methods:
An online questionnaire survey of cancer patients was conducted from February 10-29, 2020. Knowledge and practices related to COVID-19 were assessed using a custom-made questionnaire. The Hospital Anxiety and Depression Scale was used to assess the presence of anxiety and depression, with scores beyond 7 indicating anxiety or depressive disorder. Univariate and multiple linear regression analyses were used to identify the high-risk groups according to the level of knowledge, practices, anxiety, and depression scores.
Results:
A total of 341 patients were included. The rate of lower level of knowledge and practices was 49.9% and 18.8%, respectively. Education level of junior high school degree or lower showed a significant association with lower knowledge score (β: −3.503; P < 0.001) and lower practices score (β: −2.210; P < 0.001) compared to the education level of college degree and above. The prevalence of anxiety and depression among the respondents was 17.6% and 23.2%, respectively. A higher depression score was associated with older age, marital status of the widowed, and lower level of education, knowledge score, and practices score (P < 0.05).
Conclusions:
Targeted COVID-19-related education interventions are required for cancer patients with a lower level of knowledge to help improve their practices. Interventions are also required to address the anxiety and depression of cancer patients.
The significance of spiritual care competence among nurses has been emphasized across countries and cultures in many studies. However, there were few studies on correlations among spiritual care competence, spiritual care perceptions, and spiritual health of nurses in China.
Objective
To investigate spiritual care competence, spiritual care perceptions, and spiritual health, and examine the correlations among spiritual care competence, spiritual care perceptions and spiritual health, and the mediating role of spiritual health between other two variables of Chinese nurses.
Methods
A cross-sectional and correlational design was implemented, and the STROBE Checklist was used to report the study. A convenience sample of 2,181 nurses were selected from 17 hospitals in 3 provinces, China. Participants provided data on sociodemographic by completing the Chinese Version of the Spiritual Care Competence Scale, the Chinese Version of the Spiritual Care-Giving Scale, and the Spiritual Health Scale Short Form. Descriptive statistics, univariate, multiple linear regression, and Pearson correlation analysis were used to analyze data.
Results
The total scores of spiritual care competence, spiritual care perceptions, and spiritual health were 58.25 ± 16.21, 144.49 ± 16.87, and 84.88 ± 10.57, respectively, which both were moderate. Spiritual care competence was positively correlated with spiritual care perceptions (r = 0.653, p < 0.01) and spiritual health (r = 0.587, p < 0.01). And spiritual health played a mediating role between the other two variables (accounting for 35.6%).
Significance of results
The spiritual care competence, spiritual care perceptions, and spiritual health of Chinese nurses need to be improved. It is recommended that nursing managers should pay attention to spiritual care education of nurses, and improve spiritual care perceptions and spiritual health in multiple ways, so as to improve their spiritual care competence and to maximize the satisfy spiritual care needs of patients in China.
Due to less light scattering and a better signal-to-noise ratio in deep imaging, two-photon fluorescence microscopy (TPFM) has been widely used in biomedical photonics since its advent. However, optical aberrations degrade the performance of TPFM in terms of the signal intensity and the imaging depth and therefore restrict its application. Here, we introduce adaptive optics based on the genetic algorithm to detect the distorted wavefront of the excitation laser beam and then perform aberration correction to optimize the performance of TPFM. By using a spatial light modulator as the wavefront controller, the correction phase is obtained through a signal feedback loop and a process of natural selection. The experimental results show that the signal intensity and imaging depth of TPFM are improved after aberration correction. Finally, the method was applied to two-photon fluorescence lifetime imaging, which helps to improve the signal-to-noise ratio and the accuracy of lifetime analysis. Furthermore, the method can also be implemented in other experiments, such as three-photon microscopy, light-sheet microscopy, and super-resolution microscopy.
Gut microbiome and dietary patterns have been suggested to be associated with depression/anxiety. However, limited effort has been made to explore the effects of possible interactions between diet and microbiome on the risks of depression and anxiety.
Methods
Using the latest genome-wide association studies findings in gut microbiome and dietary habits, polygenic risk scores (PRSs) analysis of gut microbiome and dietary habits was conducted in the UK Biobank cohort. Logistic/linear regression models were applied for evaluating the associations for gut microbiome-PRS, dietary habits-PRS, and their interactions with depression/anxiety status and Patient Health Questionnaire (PHQ-9)/Generalized Anxiety Disorder-7 (GAD-7) score by R software.
Results
We observed 51 common diet–gut microbiome interactions shared by both PHQ score and depression status, such as overall beef intake × genus Sporobacter [hurdle binary (HB)] (PPHQ = 7.88 × 10−4, Pdepression status = 5.86 × 10−4); carbohydrate × genus Lactococcus (HB) (PPHQ = 0.0295, Pdepression status = 0.0150). We detected 41 common diet–gut microbiome interactions shared by GAD score and anxiety status, such as sugar × genus Parasutterella (rank normal transformed) (PGAD = 5.15 × 10−3, Panxiety status = 0.0347); tablespoons of raw vegetables per day × family Coriobacteriaceae (HB) (PGAD = 6.02 × 10−4, Panxiety status = 0.0345). Some common significant interactions shared by depression and anxiety were identified, such as overall beef intake × genus Sporobacter (HB).
Conclusions
Our study results expanded our understanding of how to comprehensively consider the relationships for dietary habits–gut microbiome interactions with depression and anxiety.
Tamoxifen is commonly prescribed for preventing recurrence in patients with breast cancer. However, the responses of the patients on tamoxifen treatment are variable. Cytochrome P450 genetic variants have been reported to have a significant impact on the clinical outcomes of tamoxifen treatment but no tangible conclusion can be made up till now. The present review attempts to provide a comprehensive review on the associative relationship between genetic polymorphisms in cytochrome P450 enzymes and survival in breast cancer patients on adjuvant tamoxifen therapy. The literature search was conducted using five databases, resulting in the inclusion of 58 studies in the review. An appraisal of the reporting quality of the included studies was conducted using the assessment tool from the Effective Public Health Practice Project (EPHPP). Meta-analyses were performed on CYP2D6 studies using Review Manager 5.3 software. For other studies, descriptive analyses were performed. The results of meta-analyses demonstrated that shorter overall survival, disease-free survival and relapse-free survival were found in the patients with decreased metabolisers when compared to normal metabolisers. The findings also showed that varying and conflicting results were reported by the included studies. The possible explanations for the variable results are discussed in this review.
Previous studies have suggested that maternal active smoking can increase the risk of birth defects, but evidence on second-hand tobacco smoke (SHS) is limited. We aimed to assess the association between maternal exposure to SHS and birth defects in a Chinese population. The data were based on a large-scale cross-sectional survey conducted in Shaanxi Province, China. Considering the characteristics of survey design and the potential impact of confounding factors, we adopted propensity score matching (PSM) to match the SHS exposure group and the non-exposure group to attain a balance of the confounders between the two groups. Subsequently, conditional logistic regression was employed to estimate the effect of SHS exposure on birth defects. Furthermore, sensitivity analyses were conducted to verify the key findings. After nearest neighbor matching of PSM with a ratio of 2 and a caliper width of 0.03, there were 6,205 and 12,410 participants in the exposure and control group, respectively. Pregnant women exposed to SHS were estimated to be 58% more likely to have infants with overall birth defects (OR = 1.58, 95% CI: 1.30–1.91) and 75% more likely to have infants with circulatory system defects (OR = 1.75, 95% CI: 1.26–2.44). We also observed that the risk effect of overall birth defects had an increasing trend as the frequency of exposure increased. Additionally, sensitivity analyses suggested that our results had good robustness. These results indicate that maternal exposure to SHS likely increases the risk of overall birth defects, especially circulatory system defects, in Chinese offspring.